def call_a_proc(&block)
	block.call
end
call_a_proc {puts "I'm the block... or Proc...or something"}
p = Proc.new {|x| puts x.upcase}
%w{ David Black }.each(&p)

def call_some_proc(pr)
	a = "irrelevant 'a' in method scope"
	puts a
	pr.call
end

a = "'a' to be used in Proc block"
pr = Proc.new { puts a }
pr.call
call_some_proc(pr)